Showing papers by "Jurgen Jasperneite published in 2006"

A Simulation Case Study of the new IEEE 802.11e HCCA mechanism in Industrial Wireless Networks

Abstract: The advantages of using IEEE 802.11-based wireless local area networks (WLAN) in industrial automation applications are substantial and comprise a higher flexibility, greater mobility and reduced maintenance costs. However, the currently used medium access mechanism makes WLANs non-deterministic and hence not suitable for industrial real-time traffic. The new amendment IEEE 802.11e introduces the HCF controlled channel access (HCCA) for parameterized QoS and the enhanced distributed channel access (EDCA) for prioritized QoS. This paper evaluates the performance of the HCCA in an industrial automation network with real-time requirements by means of a simulation case study with the network simulator OPNET and compares the results with the EDCA in terms of latency in various scenarios.

Potential of the HCCA scheme defined in IEEE802.11e for QoS enabled Industrial Wireless Networks

Abstract: The new draft amendment IEEE 802.11e [1] introduces an improved medium access mechanism, called HCF Controlled Channel Access (HCCA), for deterministic real-time traffic. In this paper the performance of the HCCA is evaluated in an industrial automation network with real-time requirements. Thus a simulation model of the HCCA has been implemented for the network simulator OPNET [2] and the simulation results were compared with the EDCA in terms of latency in various scenarios.

Upper time limits evaluation method for switched EthernetRTM network, involves analyzing data paths for time and non-time critical data, and carrying out evaluation of limits in relation to transmission of time data between network devices

Abstract: The method involves providing data paths (710, 910, 1011, 1112) for transmission of time and/or non-time critical data between two network devices. The data paths are analyzed for time and non time-critical data separately in relation to functional and/ or physical conditioned data processing times. An evaluation of upper time limits is carried out in relation to the transmission of time critical data between the devices. An independent claim is also included for a system for projecting of a packet switching network.